But none of that has deterred Chevron. For years, it has been snapping up exploration acreage along a geological faultline that stretches from the Baltic to the Black Sea. A crucial piece of its jigsaw fell into place in May when it won the right to negotiate a big shale gas contract in Ukraine. That left it with an almost continuous arc of concessions stretching from Bulgaria in the south-east to Poland in the north. The blocks in Romania alone cover 2,700sq km.

Chevron is pressing ahead despite strong opposition from locals. Shortly after it entered Bulgaria, the country was rocked by anti-fracking protests. In January, the Bulgarian government withdrew one of Chevron's shale exploration permits.

Some companies would be discouraged by all the opposition. But Chevron takes a long-term view. It is convinced that the economic arguments for shale will ultimately trump the environmental concerns. Chief among the former is eastern Europe's overwhelming desire to reduce its reliance on imports of Russian natural gas.

Eoin Treacy's view The evolution of unconventional gas as a major contributor to the global energy mix is proving, as predicted, to be a true game changer. As countries are increasingly posed with the challenge of high energy prices, it would appear to be only a matter of time before economics trump other concerns. Europe's agonising would be greatly ameliorated if energy companies were to address concerns about the medium to long-term integrity of concrete casing used in well bores. China is employing a different strategy. It has been aggressively attempting to acquire the expertise needed to exploit its own vast resources.

Chevron (3.3%) and Exxon Mobil (2.65%) are testing the upper sides of their respective ranges. Sustained moves to new highs will be required to reaffirm demand dominance beyond the short term.

Elsewhere in the gas sector, despite the blow taken from the YPF nationalisation and Spain's economic travails, Repsol is expected to soon announce the discovery of 2.5 trillion cubic feet of gas in Peru. The share has found at least near-term support in the region of the 2009 lows near €12. A sustained move below that level would be required to question potential for a further unwind of the oversold condition relative to the 200-day MA.